President Donald Trump declared via Twitter that he is keeping perhaps his most famous campaign promise, claiming that “MEXICO IS PAYING FOR THE WALL!” through a recent trade agreement negotiated with Mexico. But economic and trade experts we interviewed said that’s not possible.

President Donald Trump wrongly said that “nobody from this country knew” about Mexico’s value-added tax until after NAFTA was signed. A deputy U.S. trade representative at the time NAFTA was put in place said: “US policymakers, embassy officials and tax authorities were fully aware of Mexico’s VAT system.”

In announcing a tentative agreement with Mexico, President Donald Trump called Mexico “a very large trading partner” and said negotiations would now begin with Canada, which he called a “smaller segment.” But U.S. trade with Canada was about $57 billion larger than trade with Mexico in 2017.

President Donald Trump has said that what Canada has “done to our dairy farm workers is a disgrace” and that “dairy farmers in Wisconsin and upstate New York … are getting killed by NAFTA.” But that trade agreement isn’t what’s hurting farmers in the current dispute.